1. Technical Field
The present invention relates to a lens holding mechanism of spectacles, in more details, to such mechanism having an extremely simple structure that the respective lenses can be securely clamped without using a screw.
2. Prior Art
Recently, a pair of spectacles, which is wide in vision and light in weight, and shapely in form, is popular among the wearers in general, and particularly a so-called "rimless spectacles" is the most popular among them, which does not require a rim enclosing the lenses because the bridge portion symmetrically connecting a pair of lenses as well as the endpiece portions foldably hinging the temples are directly screwed onto holding apertures opened in the vicinity of the fringe sides of the lenses.
However, such prior rimless spectacles was found inconvenient in use because the clamping portions of the lenses at such holding apertures become fluctuated in no time due to the loosening of a screw or wear on the lens holes. That is to say, conventionally, the lens holding has been secured by providing a supporting piece on the bridge and endpieces to be screwed onto the lenses, and abutting such member on the side surface of the lens, thereby, preventing the rotational displacement of the clamping portions. As such rimless spectacles is very simple in structure, the bridge and endpieces thereof become susceptible to deformation under external forces, with the result that the abutment of the supporting piece to the lens side surface becomes insufficient to bring the lens holding portions into an unstable condition or fluctuation.
Nowadays, the tendency for the users, who are not satisfied with the state of the art, to demand further simplification in design and structure of the rimless spectacles, especially of the lens clamping portions thereof, has further led them to complain of the intervention of such supporting piece and demand that it should be gotten rid of.
Thus, the present invention is to provide a lens holding mechanism of spectacles having such an extremely simple structure that it can dispense with a screw so as to allow further simplification in design, which nevertheless enables the respective lenses to be clamped without fluctuation.
Further, the present invention is to provide a lens holding mechanism for spectacles which is also applicable to prescription eyeglasses, the thickness and rear-side surface curvature of which change according to the degree of vision correction to be required.